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arXiv · 2008.06594

Inefficient magnetic-field amplification in supersonic laser-plasma turbulence

A. F. A. Bott·L. Chen·G. Boutoux·T. Caillaud·A. Duval·M. Koenig·B. Khiar·I. Lantuéjoul·L. Le-Deroff·B. Reville·R. Rosch·D. Ryu·C. Spindloe·B. Vauzour·B. Villette·A. A. Schekochihin·D. Q. Lamb·P. Tzeferacos·G. Gregori·A. Casner
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Abstract

We report a laser-plasma experiment that was carried out at the LMJ-PETAL facility and realized the first magnetized, turbulent, supersonic plasma with a large magnetic Reynolds number ($\mathrm{Rm} \approx 45$) in the laboratory. Initial seed magnetic fields were amplified, but only moderately so, and did not become dynamically significant. A notable absence of magnetic energy at scales smaller than the outer scale of the turbulent cascade was also observed. Our results support the notion that moderately supersonic, low-magnetic-Prandtl-number plasma turbulence is inefficient at amplifying magnetic fields.

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A. F. A. Bott, L. Chen, G. Boutoux, T. Caillaud, A. Duval, M. Koenig, B. Khiar, I. Lantuéjoul, L. Le-Deroff, B. Reville, R. Rosch, D. Ryu, C. Spindloe, B. Vauzour, B. Villette, A. A. Schekochihin, D. Q. Lamb, P. Tzeferacos, G. Gregori, A. Casner. 2020-08-14. Inefficient magnetic-field amplification in supersonic laser-plasma turbulence. https://doi.org/10.1103/physrevlett.127.175002

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